The present invention relates to a stator deflector apparatus for deflecting coolant liquid injected from an electric motor over the windings of a stator of the electric motor, and to a method of assembling the stator deflector apparatus.
In general, prior art electric motors include a rotatable rotor and a fixed stator. Stators are normally formed of a series of thin, flat plates stacked to form a solid body. Coils or windings are positioned in pre-formed slots in the plates, extending through the stack, with ends of the coils looping at each end of the stack to form end turns. The stator is normally cooled by air blowing through passages in the stator. Coolant in the form of oil injected from the motor, has also been used to cool the stator windings. However, the oil has often been misdirected and the stator windings have not been sufficiently cooled by this method.
Further, recent technological advances in electric hybrid motors, primarily for use in automobile manufacturing, have highlighted the problem where the stator windings of the electric hybrid motors have become very hot, and conventional cooling methods have been insufficient to cool down the motors. In particular, as stated above, the oil injected from the electric hybrid motor and used to cool the stator windings has not been directed appropriately to the stator windings, and have proven insufficient in cooling the stator windings.
Accordingly, an object of the present invention is to provide a stator deflector assembly which can cool the windings of a stator of an electric motor, in particular an electric hybrid motor, without a marked increase in complexity and in cost.
To this end, the present invention includes a stator deflector assembly having a deflector formed to conform to a shape of the stator; a fluid retaining and deflecting mechanism supported by the deflector; and a holding mechanism which holds the fluid retaining and deflecting mechanism at least partially against the deflector.
The fluid retaining and deflecting mechanism is an absorbent media envelope, which is a layered rolled felt in a preferred embodiment, and the felt is wrapped over the deflector.
The holding mechanism includes cotter pins which secure the felt to the deflector by inserting the cotter pins into protrusions having recesses therein, which are molded with the deflector. Also, the holding mechanism includes heat-staked pins which are also molded with the deflector, and which protrude through the wrapped felt and are melted against the felt to secure the felt to the deflector.
In a second embodiment of the present invention, the heat-staked pins and cotter pins are replaced by an adhesive, which at least partially adheres the felt to the deflector.
In a method of assembling the apparatus for cooling the windings of a stator, the steps include molding the deflector into a shape which corresponds to a shape of the stator; folding a fluid retaining and deflecting mechanism over the deflector; adhering the fluid retaining and deflecting mechanism at least partially to the deflector; and positioning the stator deflector assembly onto the stator in the electric motor.
As stated above, the fluid retaining and deflecting mechanism is an absorbent media envelope, which is a layered rolled felt in a preferred embodiment, and the holding mechanism includes cotter pins which secure the felt to the deflector, and heat-staked pins which are also molded with the deflector.
The adhering step includes heat-staking pins disposed on the deflector against the fluid retaining and deflecting mechanism; and inserting pins through recesses within protrusions protruding from the deflector, to hold the fluid retaining and deflecting mechanism against the deflector. The adhering step also includes using an adhesive, to adhere the fluid retaining and deflecting mechanism at least partially against the deflector.
Once the assembled stator deflector apparatus is placed in the motor housing, a wire which is disposed through the heads of the cotter pins, is pulled, such that all the cotter pins are removed and the felt is released from the surface of the deflector. Thus, the stator deflector assembly is able to catch the coolant using the felt, as the coolant is injected from the motor over the stator windings. The coolant is soaked into the felt and seeps through holes in the felt to the deflector, successfully soaking the stator windings of the motor. Thus, the task of cooling the stator windings, which ensures that the electric motor operates within a safe temperature range, is achieved.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described below and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract included below, are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.